///<summary>
///load graph from map data
///</summary>
///<param name="mapData"></param>
///<returns>true if successful</returns>
public bool Load(MapData mapData)
{
Clear();
//get the number of nodes and read them in
int numNodes = mapData.NodeList.Count;
for (int n = 0; n < numNodes; ++n)
{
NavGraphNode newNode = new NavGraphNode(mapData.NodeList[n]);
//when editing graphs (with Buckland's Raven map editor), it's
//possible to end up with a situation where some of the nodes
//have been invalidated (their id's set to invalid_node_index).
//Therefore when a node of index invalid_node_index is
//encountered, it must still be added.
if (!GraphNode.IsInvalidIndex(newNode.Index))
{
AddNode(newNode);
}
else
{
Nodes.Add(newNode);
//make sure an edgelist is added for each node
Edges.Add(new LinkedList<NavGraphEdge>());
++NextNodeIndex;
}
}
//now add the edges
int numEdges = mapData.EdgeList.Count;
for (int e = 0; e < numEdges; ++e)
{
NavGraphEdge nextEdge = new NavGraphEdge(mapData.EdgeList[e]);
Edges[nextEdge.From].AddLast(nextEdge);
}
return true;
}
///<summary>
///Checks to see if an entity has moved cells. If so the data structure
///is updated accordingly
///</summary>
///<param name="ent"></param>
///<param name="oldPos"></param>
public void UpdateEntity(NavGraphNode ent, Vector2 oldPos)
{
//if the index for the old pos and the new pos are not equal then
//the entity has moved to another cell.
int oldIdx = PositionToIndex(oldPos);
int newIdx = PositionToIndex(ent.Position);
if (newIdx == oldIdx) return;
//the entity has moved into another cell so delete from current
//cell and add to new one
Cells[oldIdx].Members.Remove(ent);
Cells[newIdx].Members.Add(ent);
}
///<summary>
///Given a node this method first checks to see if the node has been
///added previously but is now inactive. If it is, it is reactivated.
///
///If the node has not been added previously, it is checked to make
///sure its index matches the next node index before being added to
///the graph
///</summary>
///<param name="node"></param>
///<returns></returns>
public int AddNode(NavGraphNode node)
{
if (node.Index < Nodes.Count)
{
//make sure the client is not trying to add a node with the same
//Id as a currently active node
Assert.Fatal(GraphNode.IsInvalidIndex(Nodes[node.Index].Index),
"SparseGraph.AddNode: Attempting to add a node with a duplicate Id");
Nodes[node.Index] = node;
return NextNodeIndex;
}
//make sure the new node has been indexed correctly
Assert.Fatal(node.Index == NextNodeIndex,
"SparseGraph.AddNode: invalid index");
Nodes.Add(node);
Edges.Add(new LinkedList<NavGraphEdge>());
return NextNodeIndex++;
}
///<summary>
///Used to add the entities to the data structure
///</summary>
///<param name="ent"></param>
public void AddEntity(NavGraphNode ent)
{
Assert.Fatal(ent != null,
"CellSpacePartition.AddEntity: ent is null");
if (ent == null)
return;
int idx = PositionToIndex(ent.Position);
Cells[idx].Members.Add(ent);
}